The Tissue Culture Core will provide primary cultures of oligodendrocytes in the Projects. Ten aims in 3 projects will utilize this faculty for as a source of cultures and 13 aims in 4 projects will use it as a source of monoclonal antibodies for immunocytochemistry in situ. Project 3 (Rosenberg) will require stage-specific cultures of oligodendrocytes to test the effect of exogenous sources of free radicals on different stages of oligodendrocytes, the involvement of 12- lipoxiygenase in the pathway of cell-death triggered by oxidant stress, and the developmental expression of free radical scavenging enzymes. Oligodendrocyte cultures will be used in Project 4 (Jensen) to characterize excitotoxicity via AMP/kainate receptors in oligodendrocytes as well as the downstream mechanisms of that toxicity. Project 5 (Vartanian) will use oligodendrocyte cultures to study the toxicity of cytokines in oligodendrocytes. The Core will be used for the production of A2B5, O1, and O4 monoclonal antibodies that will be used for immunopanning and also for the identification of early differentiating oligodendrocytes. The centralization in one laboratory will give provide a significant economy of scale in ordering and using the supplies and reagents for producing cultures, and will also allow all the labs requiring cultures to benefit from the personnel having the most expertise in producing stage-specific oligodendrocyte cultures. Redundancy in effort in producing the cultures and in producing antibodies will be avoided.